From The TimeSplitters Wiki

Mr Underwood
Unlocked by	Beat Challenge "Glimpse of Stocking"
Species	Human
Size	Normal
Accuracy	8 of 10
Agility	3 of 10
Stamina	7 of 10
Fire Proof	5 of 10
Shock Proof	5 of 10
Default AI	5 Stars
Native TimeZone	1890s
First Appearance	TS2 Story Mode
Relations	N/A
Games	TS2, TSFP

TS1 Gesture	N/A	TSFP Gesture	Appears inside of an action figure package and says "I say, it's rather warm in here."
TS2 Gallery	Mr. Underwood has debunked table-rappers and fake mystics all over England. Reports of true supernatural phenomena have brought him to Paris. He has joined forces with the lady Viola to share intelligence in the battle against Jacque de la Morte.	TSFP Gallery	Mr. Underwood reckons the undead are a load of poppysticks and cockyfiddle, or should that be poppycock and fiddlesticks? Anyway, if they do exist they had better watch out for the business end of his shotgun.

Backround

Very little information is given about Mr Underwood making him one of the more mysterious characters of the series. He appears to be from England do to his manner of speaking and his style of clothing. His motives for his actons are unknown, but we do know that he enjoys beheading zombies in his spare time. His weapon of choice is his trusty doubled barrled shotgun.

Norte Dame 1895

In Timesplitters 2, Mr. Underwood aids Viola on her mission to stop Jaques de la Morte and his fiendish plans. He helps Viola defeat The Cropolite and rescuses several of the captured Maidens, before aiding Viola in the final showdown with Jaques.

Glimpse of Stocking

In Timesplitters Future Perfect, Mr Underwood stars in one of the Timeslitters "Story" Classic Challenges. The mission breifing reads:

"It's been conniptions and collywobbles all around since Mr Underwood misplaced some important 'artistic' documents. All is not lost though, by dual wielding his trusty pistols (that's double guns to us ordinary fold) it shouldn't take too long to recover his Victorian Gentleman's magazines and make a mad dash for the time portal."