The final episode of the comedy sketch show - starring Mathew Horne and James Corden - managed just 434k (2.9%) during its half-hour slot at 10.30pm.
The episode, which guest starred Will Young, drew 383k fewer viewers than the first episode, which opened to a record breaking 817k on March 11.
Also on the multichannel stations, the final episode in the current series of Coleen's Real Women grabbed 315k (1.4%) for ITV2 during the 9pm hour, and 772k (8.6%) watched the new episode of Shameless on E4 at 11pm.
Elsewhere, All The Small Things continued to perform well for BBC One, logging 4.33m (17.6%) during the 9pm hour.
Five screening of the new CSI episode pulled in 2.63m (10.6%), just ahead of the latest visit to The Hospital, which attracted 2.6m (10.6%) to Channel 4.
BBC Two's Horse People With Alexandra Tolstoy, which saw the host meet a Spanish family who fight bulls from horseback, drew a lowly 1m (4.1%).
ITV1's coverage of Chelsea's game against Liverpool averaged an impressive 7.41m (31.2%) between 7.30pm and 10pm.
At 8pm, Holby City put in 5.43m (22.8%) for BBC One, while 2.47m (10.4%) tuned in for the first in a new series of Gok's Fashion Fix on Channel 4.
Five's Was Dr Crippen Innocent? Revealed took 1.01m (4.3%), and Jo Brand's The Speaker managed 810k (3.4%) for BBC Two.
Overall, ITV1 came top during primetime with an average share of 26.8% to BBC One's 23%. Channel 4 was third with 9.2% (+1: 0.9%), followed by Five with 6.4% and BBC Two with 4.5%.
Ratings data supplied by Attentional