"What are you-?" Monk began.

"Obstacles," Creed said, yanking more cages open.

Monk nodded, understanding. Nothing like littering their trail with scores of squealing footballs. It should slow the gunman down.

They had almost reached the far end of the vivarium when Monk heard the double doors bang open behind them. A short spatter of gunfire followed, but it quickly ended with a startled bark, followed by the clattering fall of a body to the floor.

Chalk one up for the pigskins.

Monk pushed Andrea to the end of the hall and through another set of double doors. Moments later they were back in a basement hallway.

"Those access points into the maintenance spaces," Monk pressed. "Is there one nearby?"

"The only one I know about for sure is back at Dr. Malloy's lab."

Monk studied the crisscrossing hallways and maze of rooms. He was lost. "Can you get us back there?"

"Yes. It's this way."

Andrea headed off, less shocked, more determined. Monk kept to her side. Creed followed. Monk noted him clutching his upper thigh. His pant leg was damp.

Creed met his gaze and waved him on. "Took a ricochet. Just grazed. Keep going."

They had no choice. After another turn, Monk suddenly recognized the hallway. They'd come full circle back to Dr. Malloy's lab. Confirming this, Monk spotted his briefcase resting in the hall outside the open door.

They headed toward it at a full run.

Down the opposite end of the hall, another gunman appeared with a swirl of his black rain slicker. The open lab door still lay another ten yards away.

Monk kept his arm level and fired at the assailant. "Keep going!" he yelled as Andrea and Creed slowed. "Make for the lab!"

While it might be crazy to run toward a man wielding a machine gun, the room offered the only hope of escape.

Monk fired another two rounds. He was almost out, but the shots kept the assailant off balance. Unfortunately, the brief firefight had not gone unnoticed. Behind them, a new barrage erupted. Another gunman. The attackers were trying to trap them in a crossfire.

But by now, they'd reached the lab.

Andrea and Creed dashed inside. Monk bent down as the whine of a round ripped past the crown of his head. He snatched his abandoned briefcase and rolled sideways into the laboratory.

As soon as he was through, Creed slammed the door behind him.

"Locks automatically," Andrea said, hugging her arms around her chest. She kept well clear of the chair where Dr. Malloy's body was still tied.

Monk gained his feet, holding his pistol in one hand and his Tanner Krolle briefcase in the other. "That maintenance access?"

Andrea turned and pointed toward the ceiling above a lab table. A square panel was marked by an electrical hazard symbol.

Monk turned to Creed. "Get her up there. Keep moving."

"What about you?"

"Don't worry about me. I'll be right behind you. Now move it!"

As Creed lifted Andrea onto the table, Monk dropped to one knee. He needed to buy the others as much time as possible to get away. Monk knew it was vital to get the woman to safety. Dr. Malloy must have told her something, something worth killing her over. Whatever that was, Monk wanted to know.

Creed already had the maintenance hatch open and used both arms to shove Andrea through it.

Sheltering behind the dead body in the chair, Monk snapped his briefcase and let it drop open on the floor. All the while, he kept an eye on the door. Locked or not, he knew the door would offer no more protection than a piece of tissue paper. Especially with the firepower behind these bastards.

And Monk was down to the last two rounds in his pistol. He needed the fresh magazine in his briefcase.

As he reached for the spare, the doorknob exploded into the room, along with a good section of the jamb. The door swung open from the impact.

Monk caught a fluttering glimpse of a black slicker and fired at it. Twice. His pistol slide locked open as he ran out of ammunition.

The gunman spun out of view.

Monk snatched for the new magazine while ejecting the spent one. From the corner of his eye, he spotted an arm wave beyond the doorway. A black metal object the size of a baseball flew into the room.